What’s the weirdest thing you learned this week? Well, whatever it is, we promise you’ll have an even weirder answer if you listen to PopSci’s hit podcast. The Weirdest Thing I Learned This Week hits Apple, Spotify, YouTube, and everywhere else you listen to podcasts every-other Wednesday morning. It’s your new favorite source for the strangest science-adjacent facts, figures, and Wikipedia spirals the editors of Popular Science can muster. If you like the stories in this post, we guarantee you’ll love the show.
FACT: We still don’t understand some of the most basic things about the lifecycle of American eels
By Ryan F. Mandelbaum
American and European Eels are species catadromous fish. This means that they live the opposite kind of life from a salmon—eels spend most of their life in freshwater rivers, and then spawn in the ocean. But when their hormones say it’s time to reproduce, they leave their homes in Europe and North America and all migrate to the same place: the Sargasso Sea in the Atlantic Ocean.
The Sargasso Sea is the only sea bordered on all sides by water, so named because of the vast mats of sargassum seaweed floating on its surface. It’s a patch of calm, blue water produced by a gyre of ocean currents spinning clockwise across the Atlantic. It’s an important place for fish and seabirds alike who take refuge in its seaweed, including American and European eels.
Eels start their lives as small, transparent young, called glass eels. For a long time, scientists thought that these glass eels and American/European eels were different species; it wasn’t until 19th century biologist raised the glass eels in tanks that they realized that hey matured into the big yellow-brown adults. But to this day, their lifestyle has remained a mystery—no one has found a European Eel egg or observed one spawning, for example. They just know that the little guys appear in the Sargasso.
We’re starting to learn more about the strange lives of these eels, though. For example, we now know that the adults of both species undertake the epic migration to the sargasso, dissolving their guts in order to conserve energy for the journey and dying after spawning. Scientists detected adult American eels in the Sargasso for the first time in 2015. Another team announced detecting European eels migrating to the Sargasso last year. Both American and European eels are endangered, critically endangered in the case of the latter. They’re especially vulnerable to fishing, plus the damming of the rivers where they spend their lives after spawning. So It’s more important than ever that we understand the ecology of these enigmatic fish.
FACT: ‘Bog butter’ is exactly what it sounds like, and it might just be delicious
By Rachel Feltman
In 1859, archeologists Edward Clibborn and James O’Laverty published a paper in the Ulster Journal of Archaeology titled, simply, “Bog Butter.”
“For many years past there have been found, from time to time, in the bogs of Ireland—and especially in those of the North—wooden vessels filled with butter in a hardened state, and quite free from putrefaction,” they wrote. “Specimens of these vessels, generally very much broken, are to be seen in all our museums, but until now we have never met with one in nearly a perfect state.”
But in the County of Derry, they said, they’d found a bog butter vessel in excellent shape. Based on this and other specimens, they wrote, along with what they knew about the history of Irish dairy prep, they now felt confident that the substances and pots had to do with butter churning and cheese making.
This was a huge win for the bog butter enthusiast community: in the 1800s there was simply no way to suss out the molecular makeup of butter-like substances you found buried in bogs. That didn’t stop the study authors from sampling the “yellowish white” substance they found, which they said tasted “somewhat like cheese.”
Bog butter is now considered one of the more common historical relics one might find in a bog, especially in Ireland. There have been nearly 500 reported specimens found, and the oldest known example is from 3,500 years ago. The most recent dates to as late as the 1800s, so researchers suspect the preservation method persisted in some rural pockets until pretty recently.
In 2019, researchers used stable carbon isotope analysis on the individual fatty acids in 50 bog butter samples to finally show, definitively, that there was butter in them there bogs.
So, why did people put butter into bogs? The answer is probably: lots of reasons! Why not put butter into a bog?
Researchers point out that it’s a common and misguided trope for archeologists to try to come up with a single explanation for a practice that spanned thousands of years. And not every bog butter is the same: some are in elaborate wooden vessels that predate the butter inside them by centuries, suggesting a longstanding practice of making and reusing bog butter pots, while others were seemingly dumped in without any protection. But their best guesses for those myriad reasons include protecting or hiding precious resources from enemies and authority figures (at times in Ireland you could literally pay your taxes with butter), offering up said precious dairy to gods or spirits, storing the butter to preserve it, or even using the bog process as a way of creating distinct flavors.
To find out more about why bogs are freakishly good at preserving food—and how modern scientists went about making bog butter of their own—give this week’s episode a listen.
FACT: You always get some splashback on you when peeing
By Purbita Saha
Why is peeing into a toilet or urinal so messy? This is actually a big head scratcher in fluid dynamics science. No matter how and where you pee, you’re bound to get a bit of splashback on yourself or your surroundings. This, of course, is amplified if you go no. 1 standing up. The amount of splashback also depends on the trajectory of your stream and the receptacle. Lessening the scatter effect could improve hygiene in public toilets—and make pee-recycling systems more efficient.
Surprisingly, there’s a lot of research on this topic. The Splash Lab, run by engineer Tadd Truscott, has been analyzing the behavior of pee once it rushes out of the human body for more than a decade now. Formerly based at Brigham Young University and now at Utah State University, the team uses giant spray jets and tanks to mimic the act of peeing and trace the splatter pattern of each single drop with high-speed cameras.
Their takeaway was basically that once pee is airborne, it has a mind of its own. Once it’s traveled a few inches outside the urethra, the stream begins to break up. So, when it finally reaches the inside of a toilet bowl or the back of a urinal, it hits the hard surface as thousands of individual drops. That’s when all hell breaks loose.
Depending on the angle at which you pee, plus how much and how quickly you have to relieve yourself, the force of the droplets will guarantee splashback. Closing in the distance, ideally by sitting on or squatting over the toilet, can blunt the damage. You’ll still get some pee on your netherregions, but your clothes, the seat, the floor, and, god forbid, the ceiling should be protected.
If peeing straight down isn’t an option, get as close to the receptacle as possible. Then, pee at a gently sloping downward angle so that the back of the urinal or toilet bowl still captures the bulk of the splashback. Don’t send the stream down straight into the water or drain: Making contact with another surface can cause the droplets to separate and spread out even more.
Some of the findings from the Splash Lab have helped other researchers innovate streamlined urinal designs. A recent one from the University of Waterloo, nicknamed the “Nautiloo,” is shaped like a mollusc shell with a narrow long channel, raised edges, and a curved bottom to force the pee to stream down rather than break into oodles of droplets. It was also tested for urninators of different heights, which makes a difference. Others have experimented with inserts that mimic desert moss from Mongolia to actually absorb or filter the pee to prevent splashback. But none of these are available for public restrooms or your personal bathroom just yet. So for now, it’s best to suck it up and pop a squat. And then maybe clean up after with a bidet attachment.